The answer is yes, some 3D printed objects can be toxic to humans and animals, depending on the type of material and printer used. 3D printing is a rapidly growing technology that allows users to create customized objects from digital models. However, 3D printing also poses some potential health risks, as the process of melting or curing plastic or resin can release harmful particles and chemicals into the air and the finished product. In this article, we will explore the sources, effects, and solutions of 3D printing toxicity.
There are two main types of 3D printers: fused deposition modeling (FDM) and stereolithography (SLA). FDM printers work by heating and extruding plastic filaments, layer by layer, to form a solid object. SLA printers use a laser to cure liquid resin into a solid shape. Both types of printers can emit volatile organic compounds (VOCs) and ultrafine particles (UFPs) during the printing process. VOCs are gaseous substances that can evaporate from the heated plastic or resin, such as acrylonitrile, styrene, and formaldehyde. UFPs are tiny solid particles that can become airborne from the melted or cured material, such as carbon black, titanium dioxide, and silver.
The amount and composition of VOCs and UFPs vary depending on the type of material and printer used. Generally, higher printing temperatures, longer printing durations, and smaller nozzle diameters can increase the emissions. According to a study by the Georgia Institute of Technology, acrylonitrile butadiene styrene (ABS) plastic, which requires a higher temperature to melt, produced more emissions than polylactic acid (PLA) plastic, which melts at a lower temperature. Another study by the University of California, Riverside found that parts from SLA printers were more toxic than parts from FDM printers, as the liquid resin contained more hazardous ingredients, such as acrylates, epoxies, and urethanes.
The exposure to VOCs and UFPs from 3D printing can have negative impacts on human and animal health, especially for those who work or live in close proximity to the printers. The effects can range from mild to severe, depending on the level, duration, and frequency of exposure, as well as the individual’s sensitivity and health condition.
Some of the common effects of VOCs and UFPs are:
Respiratory irritation: VOCs and UFPs can irritate the nose, throat, and lungs, causing coughing, sneezing, wheezing, and shortness of breath. They can also aggravate existing respiratory conditions, such as asthma, bronchitis, and emphysema.
Headache and dizziness: VOCs and UFPs can affect the central nervous system, causing headache, dizziness, nausea, and fatigue. They can also impair cognitive functions, such as memory, attention, and coordination.
Allergic reaction: VOCs and UFPs can trigger allergic reactions in some people, such as skin rash, eye irritation, and nasal congestion. They can also cause hypersensitivity pneumonitis, a rare lung disease that causes inflammation and scarring of the lung tissue.
Cancer: Some VOCs and UFPs are known or suspected carcinogens, meaning they can cause cancer in humans or animals. For example, acrylonitrile, styrene, and formaldehyde are classified as probable human carcinogens by the International Agency for Research on Cancer. Epoxies and urethanes are also potential carcinogens, according to the National Toxicology Program.
Solutions for 3D Printing Toxicity
The good news is that there are some ways to reduce the toxicity of 3D printing and protect yourself and others from the harmful emissions. Some of the possible solutions are:
Choose safer materials and printers: If possible, opt for materials and printers that produce lower emissions, such as PLA plastic and FDM printers. Avoid using materials and printers that require high temperatures, long durations, or small nozzles. Also, check the safety data sheets (SDS) of the materials and printers before using them, and follow the manufacturer’s instructions and recommendations.
Use ventilation and filtration: Make sure the printing area is well-ventilated and has adequate air circulation. Use an exhaust fan, a window, or an air conditioner to remove the contaminated air from the room. You can also use a high-efficiency particulate air (HEPA) filter or an activated carbon filter to capture the VOCs and UFPs from the air. Alternatively, you can enclose the printer in a box or a cabinet with a vent or a filter to prevent the emissions from escaping.
Wear personal protective equipment (PPE): When handling the printer or the printed parts, wear appropriate PPE, such as gloves, goggles, and a mask or a respirator. This can help prevent direct contact or inhalation of the VOCs and UFPs. Dispose of the PPE properly after use, and wash your hands thoroughly.
Post-process the printed parts: Some studies have suggested that post-processing the printed parts can reduce their toxicity. For example, a study by the Georgia Institute of Technology found that exposing the parts from SLA printers to ultraviolet light for 10 minutes reduced their toxicity by 99%. Another study by the University of California, Riverside found that soaking the parts from FDM printers in ethanol for one hour reduced their toxicity by 85%. However, these methods may also affect the quality and durability of the parts, so use them with caution.
3D printing is a fascinating and useful technology, but it also comes with some potential health risks. Some 3D printed objects can be toxic to humans and animals, depending on the type of material and printer used. The toxicity is mainly caused by the VOCs and UFPs that are emitted during the printing process, which can have various effects on the respiratory, nervous, immune, and reproductive systems. To minimize the toxicity of 3D printing, it is important to choose safer materials and printers, use ventilation and filtration, wear personal protective equipment, and post-process the printed parts. By following these steps, you can enjoy the benefits of 3D printing without compromising your health and safety.
